Method of increasing the production of oil-wells.



I. DUNN.

METHOD FOR INCREASING THE PRODUCTION OF OIL WELLS.

APPLICATION FILED JAN-20,19l4- Patented July 11, 1916.

NITED STATES PATENT OFFICE.

IRWIN L. DUNN, or ARIE'r'rA, OHIO, ASSIGNOR 'ro PETROLEUM. rA'rnN'rsCOMPANY,

or CHICAGO, ILL NoIs, A oonronA'rIoN or MAINE.

METHOD FOR INCREASING THE PRODUCTION or oIL-wnLLs.

Specification of Letters Patent.

Patented July 11, 1916,

Application filed January 20, 1914. Serial No. 813,159.

invented certain new and useful Improvements in Methods for-Increasingthe Production of Oil-Wells, of which the followwhich, when opened ingis a specification.

The history of practically all oil wells above the surface of the groundwithout mechanical or other assistance, is that the flow gradually orrapidly decreases with the lapse of time until ultimately it' becomesinsignificant or ceases altogether. It has long been the practice whenthe flow becomes too small to torpedo the well which consists inexploding a charge of dynamite or other high explosive at the bottom ofthe well, or where the .well traverses the oil-rock, the precise actionof which on the roclz is perresult is ordinarily to increase the flow.The beneficial eflect, however, is ofcomparatively short duration andthe next step ordinarily is to raise the oil by means of a mechanicalpump inserted in the well. It is probable, ii": not demonstrable, thatthe reason'forthe diminution in the flow of oil is not entirely, if atall, the depletion or exhaustion of the supply of-oil', but rather thatthe pressure of natural gas which is found in such wells becomes loweredto a point where it is-inefi'ective, if not to atmospheric pressure. Itis apparently a usual feature of oil bearing sand or rock bodies thatthey are each inclosed or surrounded by an impervious or substantiallyimpervious rock forming a dome or cavity which is sealed" above the oilrock. Natural gas, which usually accompanies oil and is'probably given011' by the materials from which petroleum is formed, rises by reason ofgravity to the upper portion or layers of the porousjoil sandorrockfwhere it is within the cavity and exerts a great pressure on theoil. When, therefore, the oil rock is tapped by a well the natural gasescapes through the latter together with more or less of the oil so thattheypressure is diminished as referred to above.' It has been proposedheretofore and actually practised, to imitate or substitute for theeffect of the natural gas pressure in suchwells a presat first deliverthe oil.

in great volumes sure of atmospheric air or other gas until the pressureupon the oil sand is sufliciently restored to again have an effectiveaction in driving the oil from the rock. Ordinarily, the action of thisair pressure is used only to drive the oil from the surrounding rock tothe bottom of the well or wells from which it is raised by pumpingthough of course by J supplying sufficient air under pressure it may befurther utilized to raise or assist in raising the oil in the well. Inthe usual practice of this process air under pressureis supplied to oneor more of a group of oil wells, those to which the pressure is notapplied being utilized for receiving and pumping off the oil. The airforced in finds its way to the upper" part ofthe oil sand or rock and itexerts its pressure in much the same way as the natural gas originally vfound associated with the oil, and travels, probably mainly through theupper layers of the oil rock, from theinletwell to the wells which arebeing pumped, taking or driving more or less of the oil held in thepervious rock with it. It is found that the air supplied to the rockwillpenetrate to great distances hausts and consumes the artificiallyapplied pressure at the expense of the operator supplying the same forthe benefit of his own wells, and also causes a loss of oil by him. i

It is the purpose of the present invention to largely obviate thisdifficulty by exerting adirective action upon the supplied 'airxor gasand the oil released thereby so that the I beneficial efiect of theprocess is to arlargo extent fconfined to the wells of, the operator of'the'g process' and is not wasted upon remote territory or wells uponadjacentleases of property. i

- In the accompanying drawing, I having illustrated in a diagrammaticway la suit- I practising 'my 110 able form of apparatus, for

process, though it is to be understood that the specific form ofapparatus is immaterial so long as the process as set forth in thefollowing claims is employed. The specific disclosure both of processand apparatus is for the purpose of exemplification only, the scope ofthe invention being set forth in the following claims in which I haveendeavored to distinguish it from the prior art so far as known to mewithout, however, relinquishing or abandoning any portion thereof.

The drawing represents a vertical section on a'plane through a pair ofwells which are more or less remotely located with respect to eachother.

In the well A, which represents one of a group, is inserted the usualpump B and from the upper portion of the casing G of the well a pipe Dleads to an air or gas suc-' tion pump which may be of any desired type.d

G represents a well preferably of the same group and suitably locatedwith respect to the well A, and without any oil pump but connected by apipe H with a compressor J by which air may be supplied thereto underthe desired pressure. Preferably upward of 40 pounds pressure issupplied to the well G by the compressor J as in the process heretoforeused. The air entering the oil rock tends to disperse in all directionscarrying the oil with it and flow in whichever directions areas of leastpressure exist By the operation of the suction pump E referred to above,the pressure in the wells to which it is connected and in the rock surrounding the same, is reduced below the Y normal. This region thereforehas a marked tendency to draw to it the air supplied to the well G andwith it the petroleum displaced thereby from the surrounding rock, whichfinds its way to the well .from which it is pumped. By thussupplementing the forcing of the air at the inlet well with suction atthe wells to which it is desired to drive it, a directive effect is hadupon the air and oil which causes them to flow to the desired wellswherethe oil may be pumped in the usual way. lit is found advantageous toprovide-a number of wells connected to suction along the boundaries ofthe territory being worked and especially between the pressure well andwells in adjoining territories to secure the full benefit of theoperation of the process.

I claim:

1. A process for increasing the production of oil wells consisting inforcing a gas into one of the wells of a groupunder pres- I IRWIN L. DUNN Witnesses l T. J. SUMM Rs, RUTH BITTER.

